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Conboy JP, Istúriz Petitjean I, van der Net A, Koenderink GH. How cytoskeletal crosstalk makes cells move: Bridging cell-free and cell studies. BIOPHYSICS REVIEWS 2024; 5:021307. [PMID: 38840976 PMCID: PMC11151447 DOI: 10.1063/5.0198119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024]
Abstract
Cell migration is a fundamental process for life and is highly dependent on the dynamical and mechanical properties of the cytoskeleton. Intensive physical and biochemical crosstalk among actin, microtubules, and intermediate filaments ensures their coordination to facilitate and enable migration. In this review, we discuss the different mechanical aspects that govern cell migration and provide, for each mechanical aspect, a novel perspective by juxtaposing two complementary approaches to the biophysical study of cytoskeletal crosstalk: live-cell studies (often referred to as top-down studies) and cell-free studies (often referred to as bottom-up studies). We summarize the main findings from both experimental approaches, and we provide our perspective on bridging the two perspectives to address the open questions of how cytoskeletal crosstalk governs cell migration and makes cells move.
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Affiliation(s)
- James P. Conboy
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Irene Istúriz Petitjean
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Anouk van der Net
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
| | - Gijsje H. Koenderink
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 2629 HZ Delft, The Netherlands
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2
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Troyanovsky RB, Indra I, Troyanovsky SM. Characterization of early and late events of adherens junction assembly. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.04.583373. [PMID: 38496678 PMCID: PMC10942379 DOI: 10.1101/2024.03.04.583373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Cadherins are transmembrane adhesion receptors. Cadherin ectodomains form adhesive 2D clusters through cooperative trans and cis interactions, whereas its intracellular region interacts with specific cytosolic proteins, termed catenins, to anchor the cadherin-catenin complex (CCC) to the actin cytoskeleton. How these two types of interactions are coordinated in the formation of specialized cell-cell adhesions, adherens junctions (AJ), remains unclear. We focus here on the role of the actin-binding domain of α-catenin (αABD) by showing that the interaction of αABD with actin generates actin-bound CCC oligomers (CCC/actin strands) incorporating up to six CCCs. The strands are primarily formed on the actin-rich cell protrusions. Once in cell-cell interface, the strands become involved in cadherin ectodomain clustering. Such combination of the extracellular and intracellular oligomerizations gives rise to the composite oligomers, trans CCC/actin clusters. To mature, these clusters then rearrange their actin filaments using several redundant pathways, two of which are characterized here: one depends on the α-catenin-associated protein, vinculin and the second one depends on the unstructured C-terminus of αABD. Thus, AJ assembly proceeds through spontaneous formation of trans CCC/actin clusters and their successive reorganization.
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Affiliation(s)
- Regina B Troyanovsky
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611
| | - Indrajyoti Indra
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611
| | - Sergey M Troyanovsky
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611
- Department of Cell & Developmental Biology, The Feinberg School of Medicine, Chicago, IL 60614
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3
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Troyanovsky SM. Adherens junction: the ensemble of specialized cadherin clusters. Trends Cell Biol 2023; 33:374-387. [PMID: 36127186 PMCID: PMC10020127 DOI: 10.1016/j.tcb.2022.08.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022]
Abstract
The cell-cell connections in adherens junctions (AJs) are mediated by transmembrane receptors, type I cadherins (referred to here as cadherins). These cadherin-based connections (or trans bonds) are weak. To upregulate their strength, cadherins exploit avidity, the increased affinity of binding between cadherin clusters compared with isolated monomers. Formation of such clusters is a unique molecular process that is driven by a synergy of direct and indirect cis interactions between cadherins located at the same cell. In addition to their role in adhesion, cadherin clusters provide structural scaffolds for cytosolic proteins, which implicate cadherin into different cellular activities and signaling pathways. The cluster lifetime, which depends on the actin cytoskeleton, and on the mechanical forces it generates, determines the strength of AJs and their plasticity. The key aspects of cadherin adhesion, therefore, cannot be understood at the level of isolated cadherin molecules, but should be discussed in the context of cadherin clusters.
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Affiliation(s)
- Sergey M Troyanovsky
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611, USA; Department of Cell and Molecular Biology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611, USA.
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4
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Rangarajan ES, Smith EW, Izard T. Distinct inter-domain interactions of dimeric versus monomeric α-catenin link cell junctions to filaments. Commun Biol 2023; 6:276. [PMID: 36928388 PMCID: PMC10020564 DOI: 10.1038/s42003-023-04610-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 02/17/2023] [Indexed: 03/18/2023] Open
Abstract
Attachment between cells is crucial for almost all aspects of the life of cells. These inter-cell adhesions are mediated by the binding of transmembrane cadherin receptors of one cell to cadherins of a neighboring cell. Inside the cell, cadherin binds β-catenin, which interacts with α-catenin. The transitioning of cells between migration and adhesion is modulated by α-catenin, which links cell junctions and the plasma membrane to the actin cytoskeleton. At cell junctions, a single β-catenin/α-catenin heterodimer slips along filamentous actin in the direction of cytoskeletal tension which unfolds clustered heterodimers to form catch bonds with F-actin. Outside cell junctions, α-catenin dimerizes and links the plasma membrane to F-actin. Under cytoskeletal tension, α-catenin unfolds and forms an asymmetric catch bond with F-actin. To understand the mechanism of this important α-catenin function, we determined the 2.7 Å cryogenic electron microscopy (cryoEM) structures of filamentous actin alone and bound to human dimeric α-catenin. Our structures provide mechanistic insights into the role of the α-catenin interdomain interactions in directing α-catenin function and suggest a bivalent mechanism. Further, our cryoEM structure of human monomeric α-catenin provides mechanistic insights into α-catenin autoinhibition. Collectively, our structures capture the initial α-catenin interaction with F-actin before the sensing of force, which is a crucial event in cell adhesion and human disease.
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Affiliation(s)
| | - Emmanuel W Smith
- The Cell Adhesion Laboratory, UF Scripps, Jupiter, FL, 33458, USA
| | - Tina Izard
- The Cell Adhesion Laboratory, UF Scripps, Jupiter, FL, 33458, USA.
- The Skaggs Graduate School, The Scripps Research Institute, Jupiter, FL, 33458, USA.
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Du X, Fu Y, Tian Z, Liu H, Xin H, Fu X, Wang F, Zhang H, Zeng X. Microcystin-LR accelerates follicular atresia in mice via JNK-mediated adherent junction damage of ovarian granulosa cells. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 252:114592. [PMID: 36731181 DOI: 10.1016/j.ecoenv.2023.114592] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 01/25/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Microcystin-LR (MC-LR), one of aquatic environmental contaminants with reproductive toxicity produced by cyanobacterial blooms, but its toxic effects and mechanisms on the ovary are not fully understood. Here, proteomic techniques and molecular biology experiments were performed to study the potential mechanism of MC-LR-caused ovarian toxicity. Results showed that protein expression profile of ovarian granulosa cells (KK-1) was changed by 17 μg/mL MC-LR exposure. Comparing with the control group, 118 upregulated proteins as well as 97 downregulated proteins were identified in MC-LR group. Function of differentially expressed proteins was found to be enriched in pathways related to adherent junction, such as cadherin binding, cell-cell junction, cell adhesion and focal adherens. Furthermore, in vitro experiments, MC-LR significantly downregulated the expression levels of proteins associated with adherent junction (β-catenin, N-cadherin, and α-catenin) as well as caused cytoskeletal disruption in KK-1 cells (P < 0.05), indicating that the adherent junction was damaged. Results of in vivo experiments have shown that after 14 days of acute MC-LR exposure (40 μg/kg), damaged adherent junction and an increased number of atretic follicles were observed in mouse ovaries. Moreover, MC-LR activated JNK, an upstream regulator of adherent junction proteins, in KK-1 cells and mouse ovarian tissues. In contrast, JNK inhibition alleviated MC-LR-induced adherent junction damage in vivo and in vitro, as well as the number of atretic follicles. Taken together, findings from the present study indicated that JNK is involved in MC-LR-induced granulosa cell adherent junction damage, which accelerated follicular atresia. Our study clarified a novel mechanism of MC-LR-caused ovarian toxicity, providing a theoretical foundation for protecting female reproductive health from environmental pollutants.
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Affiliation(s)
- Xingde Du
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Yu Fu
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Zhihui Tian
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Haohao Liu
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Hongxia Xin
- Henan Eye Institute, Henan Eye Hospital, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Xiaoli Fu
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Fufang Wang
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China
| | - Huizhen Zhang
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
| | - Xin Zeng
- College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
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6
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Bax NA, Wang A, Huang DL, Pokutta S, Weis WI, Dunn AR. Multi-level Force-dependent Allosteric Enhancement of αE-catenin Binding to F-actin by Vinculin. J Mol Biol 2023; 435:167969. [PMID: 36682678 PMCID: PMC9957948 DOI: 10.1016/j.jmb.2023.167969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 01/22/2023]
Abstract
Classical cadherins are transmembrane proteins whose extracellular domains link neighboring cells, and whose intracellular domains connect to the actin cytoskeleton via β-catenin and α-catenin. The cadherin-catenin complex transmits forces that drive tissue morphogenesis and wound healing. In addition, tension-dependent changes in αE-catenin conformation enables it to recruit the actin-binding protein vinculin to cell-cell junctions, which contributes to junctional strengthening. How and whether multiple cadherin-complexes cooperate to reinforce cell-cell junctions in response to load remains poorly understood. Here, we used single-molecule optical trap measurements to examine how multiple cadherin-catenin complexes interact with F-actin under load, and how this interaction is influenced by the presence of vinculin. We show that force oriented toward the (-) end of the actin filament results in mean lifetimes 3-fold longer than when force was applied towards the barbed (+) end. We also measured force-dependent actin binding by a quaternary complex comprising the cadherin-catenin complex and the vinculin head region, which cannot itself bind actin. Binding lifetimes of this quaternary complex increased as additional complexes bound F-actin, but only when load was oriented toward the (-) end. In contrast, the cadherin-catenin complex alone did not show this form of cooperativity. These findings reveal multi-level, force-dependent regulation that enhances the strength of the association of multiple cadherin/catenin complexes with F-actin, conferring positive feedback that may strengthen the junction and polarize F-actin to facilitate the emergence of higher-order cytoskeletal organization.
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Affiliation(s)
- Nicolas A Bax
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, United States. https://twitter.com/@bax1337
| | - Amy Wang
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, United States; Department of Chemical Engineering, Stanford University School of Engineering, United States. https://twitter.com/@amywang01
| | - Derek L Huang
- Graduate Program in Biophysics, Stanford University, United States
| | - Sabine Pokutta
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, United States
| | - William I Weis
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, United States.
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University School of Engineering, United States; Stanford Cardiovascular Institute, Stanford School of Medicine.
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7
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Rangarajan ES, Smith EW, Izard T. The nematode α-catenin ortholog, HMP1, has an extended α-helix when bound to actin filaments. J Biol Chem 2023; 299:102817. [PMID: 36539037 PMCID: PMC9860117 DOI: 10.1016/j.jbc.2022.102817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 12/09/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022] Open
Abstract
The regulation of cell-cell junctions during epidermal morphogenesis ensures tissue integrity, a process regulated by α-catenin. This cytoskeletal protein connects the cadherin complex to filamentous actin at cell-cell junctions. The cadherin-catenin complex plays key roles in cell physiology, organism development, and disease. While mutagenesis of Caenorhabditis elegans cadherin and catenin shows that these proteins are key for embryonic morphogenesis, we know surprisingly little about their structure and attachment to the cytoskeleton. In contrast to mammalian α-catenin that functions as a dimer or monomer, the α-catenin ortholog from C. elegans, HMP1 for humpback, is a monomer. Our cryogenic electron microscopy (cryoEM) structure of HMP1/α-catenin reveals that the amino- and carboxy-terminal domains of HMP1/α-catenin are disordered and not in contact with the remaining HMP1/α-catenin middle domain. Since the carboxy-terminal HMP1/α-catenin domain is the F-actin-binding domain (FABD), this interdomain constellation suggests that HMP1/α-catenin is constitutively active, which we confirm biochemically. Our perhaps most surprising finding, given the high sequence similarity between the mammalian and nematode proteins, is our cryoEM structure of HMP1/α-catenin bound to F-actin. Unlike the structure of mammalian α-catenin bound to F-actin, binding to F-actin seems to allosterically convert a loop region of the HMP1/α-catenin FABD to extend an HMP1/α-catenin FABD α-helix. We use cryoEM and bundling assays to show for the first time how the FABD of HMP1/α-catenin bundles actin in the absence of force. Collectively, our data advance our understanding of α-catenin regulation of cell-cell contacts and additionally aid our understanding of the evolution of multicellularity in metazoans.
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Affiliation(s)
| | | | - Tina Izard
- Cell Adhesion Laboratory, UF Scripps, Jupiter, Florida, USA; The Skaggs Graduate School, The Scripps Research Institute, Jupiter, Florida, USA.
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8
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Serre JM, Lucas B, Martin SCT, Heier JA, Shao X, Hardin J. C. elegans srGAP is an α-catenin M domain-binding protein that strengthens cadherin-dependent adhesion during morphogenesis. Development 2022; 149:dev200775. [PMID: 36125129 PMCID: PMC10655919 DOI: 10.1242/dev.200775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/23/2022] [Indexed: 11/20/2022]
Abstract
The cadherin-catenin complex (CCC) is central to embryonic development and tissue repair, yet how CCC binding partners function alongside core CCC components remains poorly understood. Here, we establish a previously unappreciated role for an evolutionarily conserved protein, the slit-robo GTPase-activating protein SRGP-1/srGAP, in cadherin-dependent morphogenetic processes in the Caenorhabditis elegans embryo. SRGP-1 binds to the M domain of the core CCC component, HMP-1/α-catenin, via its C terminus. The SRGP-1 C terminus is sufficient to target it to adherens junctions, but only during later embryonic morphogenesis, when junctional tension is known to increase. Surprisingly, mutations that disrupt stabilizing salt bridges in the M domain block this recruitment. Loss of SRGP-1 leads to an increase in mobility and decrease of junctional HMP-1. In sensitized genetic backgrounds with weakened adherens junctions, loss of SRGP-1 leads to late embryonic failure. Rescue of these phenotypes requires the C terminus of SRGP-1 but also other domains of the protein. Taken together, these data establish a role for an srGAP in stabilizing and organizing the CCC during epithelial morphogenesis by binding to a partially closed conformation of α-catenin at junctions.
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Affiliation(s)
- Joel M. Serre
- Program in Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Bethany Lucas
- Department of Biology, Regis University, 3333 Regis Blvd., Denver, CO 80221, USA
| | - Sterling C. T. Martin
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jonathon A. Heier
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Xiangqiang Shao
- Wisconsin State Laboratory of Hygiene, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jeff Hardin
- Program in Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Biophysics Graduate Program, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
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9
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Wang A, Dunn AR, Weis WI. Mechanism of the cadherin-catenin F-actin catch bond interaction. eLife 2022; 11:80130. [PMID: 35913118 PMCID: PMC9402232 DOI: 10.7554/elife.80130] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
Mechanotransduction at cell-cell adhesions is crucial for the structural integrity, organization, and morphogenesis of epithelia. At cell-cell junctions, ternary E-cadherin/β-catenin/αE-catenin complexes sense and transmit mechanical load by binding to F-actin. The interaction with F-actin, described as a two-state catch bond, is weak in solution but is strengthened by applied force due to force-dependent transitions between weak and strong actin-binding states. Here, we provide direct evidence from optical trapping experiments that the catch bond property principally resides in the αE-catenin actin-binding domain (ABD). Consistent with our previously proposed model, deletion of the first helix of the five-helix ABD bundle enables stable interactions with F-actin under minimal load that are well-described by a single-state slip bond, even when αE-catenin is complexed with β-catenin and E-cadherin. Our data argue for a conserved catch bond mechanism for adhesion proteins with structurally similar ABDs. We also demonstrate that a stably bound ABD strengthens load-dependent binding interactions between a neighboring complex and F-actin, but the presence of the other αE-catenin domains weakens this effect. These results provide mechanistic insight to the cooperative binding of the cadherin-catenin complex to F-actin, which regulate dynamic cytoskeletal linkages in epithelial tissues.
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Affiliation(s)
- Amy Wang
- Department of Chemical Engineering, Stanford University, Stanford, United States
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, United States
| | - William I Weis
- Department of Chemical Engineering, Stanford University, Stanford, United States
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Fernandez-Gonzalez R, Peifer M. Powering morphogenesis: multiscale challenges at the interface of cell adhesion and the cytoskeleton. Mol Biol Cell 2022; 33. [PMID: 35696393 DOI: 10.1091/mbc.e21-09-0452] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Among the defining features of the animal kingdom is the ability of cells to change shape and move. This underlies embryonic and postembryonic development, tissue homeostasis, regeneration, and wound healing. Cell shape change and motility require linkage of the cell's force-generating machinery to the plasma membrane at cell-cell and cell-extracellular matrix junctions. Connections of the actomyosin cytoskeleton to cell-cell adherens junctions need to be both resilient and dynamic, preventing tissue disruption during the dramatic events of embryonic morphogenesis. In the past decade, new insights radically altered the earlier simple paradigm that suggested simple linear linkage via the cadherin-catenin complex as the molecular mechanism of junction-cytoskeleton interaction. In this Perspective we provide a brief overview of our current state of knowledge and then focus on selected examples highlighting what we view as the major unanswered questions in our field and the approaches that offer exciting new insights at multiple scales from atomic structure to tissue mechanics.
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Affiliation(s)
- Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G5, Canada.,Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5S 3G5, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada.,Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Mark Peifer
- Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27599-3280.,Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280
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Cho Y, Haraguchi D, Shigetomi K, Matsuzawa K, Uchida S, Ikenouchi J. Tricellulin secures the epithelial barrier at tricellular junctions by interacting with actomyosin. J Biophys Biochem Cytol 2022; 221:213005. [PMID: 35148372 PMCID: PMC8847807 DOI: 10.1083/jcb.202009037] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 10/21/2021] [Accepted: 01/04/2022] [Indexed: 01/04/2023] Open
Abstract
The epithelial cell sheet functions as a barrier to prevent invasion of pathogens. It is necessary to eliminate intercellular gaps not only at bicellular junctions, but also at tricellular contacts, where three cells meet, to maintain epithelial barrier function. To that end, tight junctions between adjacent cells must associate as closely as possible, particularly at tricellular contacts. Tricellulin is an integral component of tricellular tight junctions (tTJs), but the molecular mechanism of its contribution to the epithelial barrier function remains unclear. In this study, we revealed that tricellulin contributes to barrier formation by regulating actomyosin organization at tricellular junctions. Furthermore, we identified α-catenin, which is thought to function only at adherens junctions, as a novel binding partner of tricellulin. α-catenin bridges tricellulin attachment to the bicellular actin cables that are anchored end-on at tricellular junctions. Thus, tricellulin mobilizes actomyosin contractility to close the lateral gap between the TJ strands of the three proximate cells that converge on tricellular junctions.
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Affiliation(s)
- Yuma Cho
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Daichi Haraguchi
- Department of Advanced Information Technology, Kyushu University, Fukuoka, Japan
| | - Kenta Shigetomi
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Kenji Matsuzawa
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Seiichi Uchida
- Department of Advanced Information Technology, Kyushu University, Fukuoka, Japan
| | - Junichi Ikenouchi
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
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12
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α-catenin switches between a slip and an asymmetric catch bond with F-actin to cooperatively regulate cell junction fluidity. Nat Commun 2022; 13:1146. [PMID: 35241656 PMCID: PMC8894357 DOI: 10.1038/s41467-022-28779-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 02/10/2022] [Indexed: 12/11/2022] Open
Abstract
α-catenin is a crucial protein at cell junctions that provides connection between the actin cytoskeleton and the cell membrane. At adherens junctions (AJs), α-catenin forms heterodimers with β-catenin that are believed to resist force on F-actin. Outside AJs, α-catenin forms homodimers that regulates F-actin organization and directly connect the cell membrane to the actin cytoskeleton, but their mechanosensitive properties are inherently unknown. By using ultra-fast laser tweezers we found that a single α-β-catenin heterodimer does not resist force but instead slips along F-actin in the direction of force. Conversely, the action of 5 to 10 α-β-catenin heterodimers together with force applied toward F-actin pointed end engaged a molecular switch in α-catenin, which unfolded and strongly bound F-actin as a cooperative catch bond. Similarly, an α-catenin homodimer formed an asymmetric catch bond with F-actin triggered by protein unfolding under force. Our data suggest that α-catenin clustering together with intracellular tension engage a fluid-to-solid phase transition at the membrane-cytoskeleton interface.
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13
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Cortical tension initiates the positive feedback loop between cadherin and F-actin. Biophys J 2022; 121:596-606. [PMID: 35031276 PMCID: PMC8874026 DOI: 10.1016/j.bpj.2022.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/30/2021] [Accepted: 01/10/2022] [Indexed: 11/20/2022] Open
Abstract
Adherens junctions physically link two cells at their contact interface via extracellular binding between cadherin molecules and intracellular interactions between cadherins and the actin cytoskeleton. Cadherin and actomyosin cytoskeletal dynamics are regulated reciprocally by mechanical and chemical signals, which subsequently determine the strength of cell-cell adhesions and the emergent organization and stiffness of the tissues they form. However, an understanding of the integrated system is lacking. We present a new mechanistic computational model of intercellular junction maturation in a cell doublet to investigate the mechanochemical cross talk that regulates adherens junction formation and homeostasis. The model couples a two-dimensional lattice-based simulation of cadherin dynamics with a reaction-diffusion representation of the reorganising actomyosin network through its regulation by Rho signalling at the intracellular junction. We demonstrate that local immobilization of cadherin induces cluster formation in a cis-less-dependent manner. We then recapitulate the process of cell-cell contact formation. Our model suggests that cortical tension applied on the contact rim can explain the ring distribution of cadherin and actin filaments (F-actin) on the cell-cell contact of the cell doublet. Furthermore, we propose and test the hypothesis that cadherin and F-actin interact like a positive feedback loop, which is necessary for formation of the ring structure. Different patterns of cadherin distribution were observed as an emergent property of disturbances of this positive feedback loop. We discuss these findings in light of available experimental observations on underlying mechanisms related to cadherin/F-actin binding and the mechanical environment.
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14
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Abstract
E-cadherin is the main component of epithelial adherens junctions (AJs), which play a crucial role in the maintenance of stable cell-cell adhesion and overall tissue integrity. Down-regulation of E-cadherin expression has been found in many carcinomas, and loss of E-cadherin is generally associated with poor prognosis in patients. During the last decade, however, numerous studies have shown that E-cadherin is essential for several aspects of cancer cell biology that contribute to cancer progression, most importantly, active cell migration. In this review, we summarize the available data about the input of E-cadherin in cancer progression, focusing on the latest advances in the research of the various roles E-cadherin-based AJs play in cancer cell dissemination. The review also touches upon the "cadherin switching" in cancer cells where N- or P-cadherin replace or are co-expressed with E-cadherin and its influence on the migratory properties of cancer cells.
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Affiliation(s)
- Svetlana N Rubtsova
- N.N. Blokhin National Medical Research Center of Oncology, Institute of Carcinogenesis, Moscow, Russia
| | - Irina Y Zhitnyak
- N.N. Blokhin National Medical Research Center of Oncology, Institute of Carcinogenesis, Moscow, Russia
| | - Natalya A Gloushankova
- N.N. Blokhin National Medical Research Center of Oncology, Institute of Carcinogenesis, Moscow, Russia
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15
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Schink KO, Tan KW, Spangenberg H, Martorana D, Sneeggen M, Stévenin V, Enninga J, Campsteijn C, Raiborg C, Stenmark H. The phosphoinositide coincidence detector Phafin2 promotes macropinocytosis by coordinating actin organisation at forming macropinosomes. Nat Commun 2021; 12:6577. [PMID: 34772942 PMCID: PMC8590015 DOI: 10.1038/s41467-021-26775-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 10/08/2021] [Indexed: 01/14/2023] Open
Abstract
Uptake of large volumes of extracellular fluid by actin-dependent macropinocytosis has an important role in infection, immunity and cancer development. A key question is how actin assembly and disassembly are coordinated around macropinosomes to allow them to form and subsequently pass through the dense actin network underlying the plasma membrane to move towards the cell center for maturation. Here we show that the PH and FYVE domain protein Phafin2 is recruited transiently to newly-formed macropinosomes by a mechanism that involves coincidence detection of PtdIns3P and PtdIns4P. Phafin2 also interacts with actin via its PH domain, and recruitment of Phafin2 coincides with actin reorganization around nascent macropinosomes. Moreover, forced relocalization of Phafin2 to the plasma membrane causes rearrangement of the subcortical actin cytoskeleton. Depletion of Phafin2 inhibits macropinosome internalization and maturation and prevents KRAS-transformed cancer cells from utilizing extracellular protein as an amino acid source. We conclude that Phafin2 promotes macropinocytosis by controlling timely delamination of actin from nascent macropinosomes for their navigation through the dense subcortical actin network.
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Affiliation(s)
- Kay Oliver Schink
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway.
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway.
| | - Kia Wee Tan
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Hélène Spangenberg
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Domenica Martorana
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Marte Sneeggen
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Virginie Stévenin
- Department of Cell and Chemical Biology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
- Institut Pasteur, Dynamics of Host-Pathogen Interactions Unit, 25 Rue du Dr. Roux, Paris, France
| | - Jost Enninga
- Institut Pasteur, Dynamics of Host-Pathogen Interactions Unit, 25 Rue du Dr. Roux, Paris, France
| | - Coen Campsteijn
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, PO Box 1112 Blindern, 0317, Oslo, Norway
| | - Camilla Raiborg
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Montebello, N-0379, Oslo, Norway.
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379, Oslo, Norway.
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16
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Wagener BM, Hu R, Wu S, Pittet JF, Ding Q, Che P. The Role of Pseudomonas aeruginosa Virulence Factors in Cytoskeletal Dysregulation and Lung Barrier Dysfunction. Toxins (Basel) 2021; 13:776. [PMID: 34822560 PMCID: PMC8625199 DOI: 10.3390/toxins13110776] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/24/2021] [Accepted: 10/28/2021] [Indexed: 12/19/2022] Open
Abstract
Pseudomonas (P.) aeruginosa is an opportunistic pathogen that causes serious infections and hospital-acquired pneumonia in immunocompromised patients. P. aeruginosa accounts for up to 20% of all cases of hospital-acquired pneumonia, with an attributable mortality rate of ~30-40%. The poor clinical outcome of P. aeruginosa-induced pneumonia is ascribed to its ability to disrupt lung barrier integrity, leading to the development of lung edema and bacteremia. Airway epithelial and endothelial cells are important architecture blocks that protect the lung from invading pathogens. P. aeruginosa produces a number of virulence factors that can modulate barrier function, directly or indirectly, through exploiting cytoskeleton networks and intercellular junctional complexes in eukaryotic cells. This review summarizes the current knowledge on P. aeruginosa virulence factors, their effects on the regulation of the cytoskeletal network and associated components, and molecular mechanisms regulating barrier function in airway epithelial and endothelial cells. A better understanding of these processes will help to lay the foundation for new therapeutic approaches against P. aeruginosa-induced pneumonia.
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Affiliation(s)
- Brant M. Wagener
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Division of Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Ruihan Hu
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Department of Internal Medicine, Guiqian International General Hospital, Guiyang 550024, China
| | - Songwei Wu
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Jean-Francois Pittet
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Division of Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Qiang Ding
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Pulin Che
- Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (B.M.W.); (R.H.); (S.W.); (J.-F.P.); (Q.D.)
- Division of Molecular and Translational Biomedicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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17
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Arslan FN, Eckert J, Schmidt T, Heisenberg CP. Holding it together: when cadherin meets cadherin. Biophys J 2021; 120:4182-4192. [PMID: 33794149 PMCID: PMC8516678 DOI: 10.1016/j.bpj.2021.03.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/12/2021] [Accepted: 03/17/2021] [Indexed: 12/21/2022] Open
Abstract
Intercellular adhesion is the key to multicellularity, and its malfunction plays an important role in various developmental and disease-related processes. Although it has been intensively studied by both biologists and physicists, a commonly accepted definition of cell-cell adhesion is still being debated. Cell-cell adhesion has been described at the molecular scale as a function of adhesion receptors controlling binding affinity, at the cellular scale as resistance to detachment forces or modulation of surface tension, and at the tissue scale as a regulator of cellular rearrangements and morphogenesis. In this review, we aim to summarize and discuss recent advances in the molecular, cellular, and theoretical description of cell-cell adhesion, ranging from biomimetic models to the complexity of cells and tissues in an organismal context. In particular, we will focus on cadherin-mediated cell-cell adhesion and the role of adhesion signaling and mechanosensation therein, two processes central for understanding the biological and physical basis of cell-cell adhesion.
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Affiliation(s)
- Feyza Nur Arslan
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Julia Eckert
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands
| | - Thomas Schmidt
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands
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18
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Troyanovsky RB, Sergeeva AP, Indra I, Chen CS, Kato R, Shapiro L, Honig B, Troyanovsky SM. Sorting of cadherin-catenin-associated proteins into individual clusters. Proc Natl Acad Sci U S A 2021; 118:e2105550118. [PMID: 34272290 PMCID: PMC8307379 DOI: 10.1073/pnas.2105550118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The cytoplasmic tails of classical cadherins form a multiprotein cadherin-catenin complex (CCC) that constitutes the major structural unit of adherens junctions (AJs). The CCC in AJs forms junctional clusters, "E clusters," driven by cis and trans interactions in the cadherin ectodomain and stabilized by α-catenin-actin interactions. Additional proteins are known to bind to the cytoplasmic region of the CCC. Here, we analyze how these CCC-associated proteins (CAPs) integrate into cadherin clusters and how they affect the clustering process. Using a cross-linking approach coupled with mass spectrometry, we found that the majority of CAPs, including the force-sensing protein vinculin, interact with CCCs outside of AJs. Accordingly, structural modeling shows that there is not enough space for CAPs the size of vinculin to integrate into E clusters. Using two CAPs, scribble and erbin, as examples, we provide evidence that these proteins form separate clusters, which we term "C clusters." As proof of principle, we show, by using cadherin ectodomain monoclonal antibodies (mAbs), that mAb-bound E-cadherin forms separate clusters that undergo trans interactions. Taken together, our data suggest that, in addition to its role in cell-cell adhesion, CAP-driven CCC clustering serves to organize cytoplasmic proteins into distinct domains that may synchronize signaling networks of neighboring cells within tissues.
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Affiliation(s)
- Regina B Troyanovsky
- Department of Dermatology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Alina P Sergeeva
- Department of Systems Biology, Columbia University Medical Center, New York, NY 10032
| | - Indrajyoti Indra
- Department of Dermatology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Chi-Shuo Chen
- Department of Dermatology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Rei Kato
- Department of Dermatology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Lawrence Shapiro
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027
| | - Barry Honig
- Department of Systems Biology, Columbia University Medical Center, New York, NY 10032;
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027
- Department of Medicine, Columbia University, New York, NY 10032
| | - Sergey M Troyanovsky
- Department of Dermatology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611;
- Department of Cell and Developmental Biology, The Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
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19
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Heier JA, Pokutta S, Dale IW, Kim SK, Hinck AP, Weis WI, Kwiatkowski AV. Distinct intramolecular interactions regulate autoinhibition of vinculin binding in αT-catenin and αE-catenin. J Biol Chem 2021; 296:100582. [PMID: 33771561 PMCID: PMC8091058 DOI: 10.1016/j.jbc.2021.100582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 03/16/2021] [Accepted: 03/22/2021] [Indexed: 12/24/2022] Open
Abstract
α-Catenin binds directly to β-catenin and connects the cadherin–catenin complex to the actin cytoskeleton. Tension regulates α-catenin conformation. Actomyosin-generated force stretches the middle (M)-region to relieve autoinhibition and reveal a binding site for the actin-binding protein vinculin. It is not known whether the intramolecular interactions that regulate epithelial (αE)-catenin binding are conserved across the α-catenin family. Here, we describe the biochemical properties of testes (αT)-catenin, an α-catenin isoform critical for cardiac function and how intramolecular interactions regulate vinculin-binding autoinhibition. Isothermal titration calorimetry showed that αT-catenin binds the β-catenin–N-cadherin complex with a similar low nanomolar affinity to that of αE-catenin. Limited proteolysis revealed that the αT-catenin M-region adopts a more open conformation than αE-catenin. The αT-catenin M-region binds the vinculin N-terminus with low nanomolar affinity, indicating that the isolated αT-catenin M-region is not autoinhibited and thereby distinct from αE-catenin. However, the αT-catenin head (N- and M-regions) binds vinculin 1000-fold more weakly (low micromolar affinity), indicating that the N-terminus regulates the M-region binding to vinculin. In cells, αT-catenin recruitment of vinculin to cell–cell contacts requires the actin-binding domain and actomyosin-generated tension, indicating that force regulates vinculin binding. Together, our results show that the αT-catenin N-terminus is required to maintain M-region autoinhibition and modulate vinculin binding. We postulate that the unique molecular properties of αT-catenin allow it to function as a scaffold for building specific adhesion complexes.
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Affiliation(s)
- Jonathon A Heier
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sabine Pokutta
- Department of Structural Biology, Stanford University, Stanford, California, USA; Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, USA
| | - Ian W Dale
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sun Kyung Kim
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh Pennsylvania, USA
| | - Andrew P Hinck
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh Pennsylvania, USA
| | - William I Weis
- Department of Structural Biology, Stanford University, Stanford, California, USA; Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, USA
| | - Adam V Kwiatkowski
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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20
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Indra I, Troyanovsky RB, Shapiro L, Honig B, Troyanovsky SM. Sensing Actin Dynamics through Adherens Junctions. Cell Rep 2021; 30:2820-2833.e3. [PMID: 32101754 DOI: 10.1016/j.celrep.2020.01.106] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/23/2019] [Accepted: 01/29/2020] [Indexed: 11/19/2022] Open
Abstract
We study punctate adherens junctions (pAJs) to determine how short-lived cadherin clusters and relatively stable actin bundles interact despite differences in dynamics. We show that pAJ-linked bundles consist of two distinct regions-the bundle stalk (AJ-BS) and a tip (AJ-BT) positioned between cadherin clusters and the stalk. The tip differs from the stalk in a number of ways: it is devoid of the actin-bundling protein calponin, and exhibits a much faster F-actin turnover rate. While F-actin in the stalk displays centripetal movement, the F-actin in the tip is immobile. The F-actin turnover in both the tip and stalk is dependent on cadherin cluster stability, which in turn is regulated by F-actin. The close bidirectional coupling between the stability of cadherin and associated F-actin shows how pAJs, and perhaps other AJs, allow cells to sense and coordinate the dynamics of the actin cytoskeleton in neighboring cells-a mechanism we term "dynasensing."
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Affiliation(s)
- Indrajyoti Indra
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Regina B Troyanovsky
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Lawrence Shapiro
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, NY 10032, USA.
| | - Barry Honig
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Department of Systems Biology, Columbia University, New York, NY 10032, USA; Howard Hughes Medical Institute, Columbia University, New York, NY 10032, USA; Department of Medicine, Columbia University, New York, NY 10032, USA; Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, NY 10032, USA.
| | - Sergey M Troyanovsky
- Department of Dermatology, Northwestern University, The Feinberg School of Medicine, Chicago, IL 60611, USA.
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21
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Harris AR, Jreij P, Belardi B, Joffe AM, Bausch AR, Fletcher DA. Biased localization of actin binding proteins by actin filament conformation. Nat Commun 2020; 11:5973. [PMID: 33239610 PMCID: PMC7688639 DOI: 10.1038/s41467-020-19768-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 10/30/2020] [Indexed: 11/09/2022] Open
Abstract
The assembly of actin filaments into distinct cytoskeletal structures plays a critical role in cell physiology, but how proteins localize differentially to these structures within a shared cytoplasm remains unclear. Here, we show that the actin-binding domains of accessory proteins can be sensitive to filament conformational changes. Using a combination of live cell imaging and in vitro single molecule binding measurements, we show that tandem calponin homology domains (CH1-CH2) can be mutated to preferentially bind actin networks at the front or rear of motile cells. We demonstrate that the binding kinetics of CH1-CH2 domain mutants varies as actin filament conformation is altered by perturbations that include stabilizing drugs and other binding proteins. These findings suggest that conformational changes of actin filaments in cells could help to direct accessory binding proteins to different actin cytoskeletal structures through a biophysical feedback loop.
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Affiliation(s)
- Andrew R Harris
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Pamela Jreij
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Brian Belardi
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Aaron M Joffe
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Andreas R Bausch
- Lehrstuhl für Biophysik (E27), Technische Universität München, Garching, 85748, Germany
| | - Daniel A Fletcher
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA.
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA.
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22
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Mei L, Espinosa de Los Reyes S, Reynolds MJ, Leicher R, Liu S, Alushin GM. Molecular mechanism for direct actin force-sensing by α-catenin. eLife 2020; 9:62514. [PMID: 32969337 PMCID: PMC7588232 DOI: 10.7554/elife.62514] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 09/21/2020] [Indexed: 12/13/2022] Open
Abstract
The actin cytoskeleton mediates mechanical coupling between cells and their tissue microenvironments. The architecture and composition of actin networks are modulated by force; however, it is unclear how interactions between actin filaments (F-actin) and associated proteins are mechanically regulated. Here we employ both optical trapping and biochemical reconstitution with myosin motor proteins to show single piconewton forces applied solely to F-actin enhance binding by the human version of the essential cell-cell adhesion protein αE-catenin but not its homolog vinculin. Cryo-electron microscopy structures of both proteins bound to F-actin reveal unique rearrangements that facilitate their flexible C-termini refolding to engage distinct interfaces. Truncating α-catenin’s C-terminus eliminates force-activated F-actin binding, and addition of this motif to vinculin confers force-activated binding, demonstrating that α-catenin’s C-terminus is a modular detector of F-actin tension. Our studies establish that piconewton force on F-actin can enhance partner binding, which we propose mechanically regulates cellular adhesion through α-catenin. All of the cells in our bodies rely on cues from their surrounding environment to alter their behavior. As well sending each other chemical signals, such as hormones, cells can also detect pressure and physical forces applied by the cells around them. These physical interactions are coordinated by a network of proteins called the cytoskeleton, which provide the internal scaffold that maintains a cell’s shape. However, it is not well understood how forces transmitted through the cytoskeleton are converted into mechanical signals that control cell behavior. The cytoskeleton is primarily made up protein filaments called actin, which are frequently under tension from external and internal forces that push and pull on the cell. Many proteins bind directly to actin, including adhesion proteins that allow the cell to ‘stick’ to its surroundings. One possibility is that when actin filaments feel tension, they convert this into a mechanical signal by altering how they bind to other proteins. To test this theory, Mei et al. isolated and studied an adhesion protein called α-catenin which is known to interact with actin. This revealed that when tiny forces – similar to the amount cells experience in the body – were applied to actin filaments, this caused α-catenin and actin to bind together more strongly. However, applying the same level of physical force did not alter how well actin bound to a similar adhesion protein called vinculin. Further experiments showed that this was due to differences in a small, flexible region found on both proteins. Manipulating this region revealed that it helps α-catenin attach to actin when a force is present, and was thus named a ‘force detector’. Proteins that bind to actin are essential in all animals, making it likely that force detectors are a common mechanism. Scientists can now use this discovery to identify and manipulate force detectors in other proteins across different cells and animals. This may help to develop drugs that target the mechanical signaling process, although this will require further understanding of how force detectors work at the molecular level.
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Affiliation(s)
- Lin Mei
- Laboratory of Structural Biophysics and Mechanobiology, The Rockefeller University, New York, United States.,Tri-Institutional PhD Program in Chemical Biology, The Rockefeller University, New York, United States
| | | | - Matthew J Reynolds
- Laboratory of Structural Biophysics and Mechanobiology, The Rockefeller University, New York, United States
| | - Rachel Leicher
- Tri-Institutional PhD Program in Chemical Biology, The Rockefeller University, New York, United States.,Laboratory of Nanoscale Biophysics and Biochemistry, The Rockefeller University, New York, United States
| | - Shixin Liu
- Laboratory of Nanoscale Biophysics and Biochemistry, The Rockefeller University, New York, United States
| | - Gregory M Alushin
- Laboratory of Structural Biophysics and Mechanobiology, The Rockefeller University, New York, United States
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23
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Xu XP, Pokutta S, Torres M, Swift MF, Hanein D, Volkmann N, Weis WI. Structural basis of αE-catenin-F-actin catch bond behavior. eLife 2020; 9:e60878. [PMID: 32915141 PMCID: PMC7588230 DOI: 10.7554/elife.60878] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 09/09/2020] [Indexed: 11/13/2022] Open
Abstract
Cell-cell and cell-matrix junctions transmit mechanical forces during tissue morphogenesis and homeostasis. α-Catenin links cell-cell adhesion complexes to the actin cytoskeleton, and mechanical load strengthens its binding to F-actin in a direction-sensitive manner. Specifically, optical trap experiments revealed that force promotes a transition between weak and strong actin-bound states. Here, we describe the cryo-electron microscopy structure of the F-actin-bound αE-catenin actin-binding domain, which in solution forms a five-helix bundle. In the actin-bound structure, the first helix of the bundle dissociates and the remaining four helices and connecting loops rearrange to form the interface with actin. Deletion of the first helix produces strong actin binding in the absence of force, suggesting that the actin-bound structure corresponds to the strong state. Our analysis explains how mechanical force applied to αE-catenin or its homolog vinculin favors the strongly bound state, and the dependence of catch bond strength on the direction of applied force.
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Affiliation(s)
| | - Sabine Pokutta
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of MedicineStanfordUnited States
| | - Megan Torres
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of MedicineStanfordUnited States
| | | | - Dorit Hanein
- Scintillon InstituteSan DiegoUnited States
- Department of Structural Biology and Chemistry, Pasteur InstituteParisFrance
| | - Niels Volkmann
- Scintillon InstituteSan DiegoUnited States
- Department of Structural Biology and Chemistry, Pasteur InstituteParisFrance
| | - William I Weis
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of MedicineStanfordUnited States
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24
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A Weak Link with Actin Organizes Tight Junctions to Control Epithelial Permeability. Dev Cell 2020; 54:792-804.e7. [PMID: 32841596 DOI: 10.1016/j.devcel.2020.07.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 05/23/2020] [Accepted: 07/29/2020] [Indexed: 01/13/2023]
Abstract
In vertebrates, epithelial permeability is regulated by the tight junction (TJ) formed by specialized adhesive membrane proteins, adaptor proteins, and the actin cytoskeleton. Despite the TJ's critical physiological role, a molecular-level understanding of how TJ assembly sets the permeability of epithelial tissue is lacking. Here, we identify a 28-amino-acid sequence in the TJ adaptor protein ZO-1, which is responsible for actin binding, and show that this interaction is essential for TJ permeability. In contrast to the strong interactions at the adherens junction, we find that the affinity between ZO-1 and actin is surprisingly weak, and we propose a model based on kinetic trapping to explain how affinity could affect TJ assembly. Finally, by tuning the affinity of ZO-1 to actin, we demonstrate that epithelial monolayers can be engineered with a spectrum of permeabilities, which points to a promising target for treating transport disorders and improving drug delivery.
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25
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Long-Range and Directional Allostery of Actin Filaments Plays Important Roles in Various Cellular Activities. Int J Mol Sci 2020; 21:ijms21093209. [PMID: 32370032 PMCID: PMC7246755 DOI: 10.3390/ijms21093209] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/27/2020] [Accepted: 04/30/2020] [Indexed: 12/18/2022] Open
Abstract
A wide variety of uniquely localized actin-binding proteins (ABPs) are involved in various cellular activities, such as cytokinesis, migration, adhesion, morphogenesis, and intracellular transport. In a micrometer-scale space such as the inside of cells, protein molecules diffuse throughout the cell interior within seconds. In this condition, how can ABPs selectively bind to particular actin filaments when there is an abundance of actin filaments in the cytoplasm? In recent years, several ABPs have been reported to induce cooperative conformational changes to actin filaments allowing structural changes to propagate along the filament cables uni- or bidirectionally, thereby regulating the subsequent binding of ABPs. Such propagation of ABP-induced cooperative conformational changes in actin filaments may be advantageous for the elaborate regulation of cellular activities driven by actin-based machineries in the intracellular space, which is dominated by diffusion. In this review, we focus on long-range allosteric regulation driven by cooperative conformational changes of actin filaments that are evoked by binding of ABPs, and discuss roles of allostery of actin filaments in narrow intracellular spaces.
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Abstract
Epithelial cells form highly organized polarized sheets with characteristic cell morphologies and tissue architecture. Cell–cell adhesion and intercellular communication are prerequisites of such cohesive sheets of cells, and cell connectivity is mediated through several junctional assemblies, namely desmosomes, adherens, tight and gap junctions. These cell–cell junctions form signalling hubs that not only mediate cell–cell adhesion but impact on multiple aspects of cell behaviour, helping to coordinate epithelial cell shape, polarity and function. This review will focus on the tight and adherens junctions, constituents of the apical junctional complex, and aims to provide a comprehensive overview of the complex signalling that underlies junction assembly, integrity and plasticity.
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Affiliation(s)
- Alexandra D Rusu
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
| | - Marios Georgiou
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
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27
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Harris AR, Belardi B, Jreij P, Wei K, Shams H, Bausch A, Fletcher DA. Steric regulation of tandem calponin homology domain actin-binding affinity. Mol Biol Cell 2019; 30:3112-3122. [PMID: 31693446 PMCID: PMC6938246 DOI: 10.1091/mbc.e19-06-0317] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 10/03/2019] [Accepted: 10/29/2019] [Indexed: 11/11/2022] Open
Abstract
Tandem calponin homology (CH1-CH2) domains are common actin-binding domains in proteins that interact with and organize the actin cytoskeleton. Despite regions of high sequence similarity, CH1-CH2 domains can have remarkably different actin-binding properties, with disease-associated point mutants known to increase as well as decrease affinity for F-actin. To investigate features that affect CH1-CH2 affinity for F-actin in cells and in vitro, we perturbed the utrophin actin-binding domain by making point mutations at the CH1-CH2 interface, replacing the linker domain, and adding a polyethylene glycol (PEG) polymer to CH2. Consistent with a previous model describing CH2 as a steric negative regulator of actin binding, we find that utrophin CH1-CH2 affinity is both increased and decreased by modifications that change the effective "openness" of CH1 and CH2 in solution. We also identified interface mutations that caused a large increase in affinity without changing solution "openness," suggesting additional influences on affinity. Interestingly, we also observe nonuniform subcellular localization of utrophin CH1-CH2 that depends on the N-terminal flanking region but not on bulk affinity. These observations provide new insights into how small sequence changes, such as those found in diseases, can affect CH1-CH2 binding properties.
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Affiliation(s)
- Andrew R. Harris
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Brian Belardi
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Pamela Jreij
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Kathy Wei
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Hengameh Shams
- Department of Mechanical Engineering, University of California, Berkeley, Berkeley, CA 94720
| | - Andreas Bausch
- Lehrstuhl für Biophysik (E27), Technische Universität München, Garching 85748, Germany
| | - Daniel A. Fletcher
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Chan Zuckerberg Biohub, San Francisco, CA 94158
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28
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Lough KJ, Byrd KM, Descovich CP, Spitzer DC, Bergman AJ, Beaudoin GM, Reichardt LF, Williams SE. Telophase correction refines division orientation in stratified epithelia. eLife 2019; 8:49249. [PMID: 31833472 PMCID: PMC6959978 DOI: 10.7554/elife.49249] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 12/12/2019] [Indexed: 02/06/2023] Open
Abstract
During organogenesis, precise control of spindle orientation balances proliferation and differentiation. In the developing murine epidermis, planar and perpendicular divisions yield symmetric and asymmetric fate outcomes, respectively. Classically, division axis specification involves centrosome migration and spindle rotation, events occurring early in mitosis. Here, we identify a novel orientation mechanism which corrects erroneous anaphase orientations during telophase. The directionality of reorientation correlates with the maintenance or loss of basal contact by the apical daughter. While the scaffolding protein LGN is known to determine initial spindle positioning, we show that LGN also functions during telophase to reorient oblique divisions toward perpendicular. The fidelity of telophase correction also relies on the tension-sensitive adherens junction proteins vinculin, α-E-catenin, and afadin. Failure of this corrective mechanism impacts tissue architecture, as persistent oblique divisions induce precocious, sustained differentiation. The division orientation plasticity provided by telophase correction may enable progenitors to adapt to local tissue needs.
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Affiliation(s)
- Kendall J Lough
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States
| | - Kevin M Byrd
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States.,Department of Oral & Craniofacial Health Sciences, The University of North Carolina School of Dentistry, Chapel Hill, United States
| | - Carlos P Descovich
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States
| | - Danielle C Spitzer
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States
| | - Abby J Bergman
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States
| | - Gerard Mj Beaudoin
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, United States.,Department of Physiology, University of California, San Francisco, San Francisco, United States
| | - Louis F Reichardt
- Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, United States.,Department of Physiology, University of California, San Francisco, San Francisco, United States
| | - Scott E Williams
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, The University of North Carolina, Chapel Hill, United States.,Department of Biology, Lineberger Comprehensive Cancer Centre, The University of North Carolina, Chapel Hill, United States
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29
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Terekhova K, Pokutta S, Kee YS, Li J, Tajkhorshid E, Fuller G, Dunn AR, Weis WI. Binding partner- and force-promoted changes in αE-catenin conformation probed by native cysteine labeling. Sci Rep 2019; 9:15375. [PMID: 31653927 PMCID: PMC6814714 DOI: 10.1038/s41598-019-51816-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/04/2019] [Indexed: 12/12/2022] Open
Abstract
Adherens Junctions (AJs) are cell-cell adhesion complexes that sense and propagate mechanical forces by coupling cadherins to the actin cytoskeleton via β-catenin and the F-actin binding protein αE-catenin. When subjected to mechanical force, the cadherin•catenin complex can tightly link to F-actin through αE-catenin, and also recruits the F-actin-binding protein vinculin. In this study, labeling of native cysteines combined with mass spectrometry revealed conformational changes in αE-catenin upon binding to the E-cadherin•β-catenin complex, vinculin and F-actin. A method to apply physiologically meaningful forces in solution revealed force-induced conformational changes in αE-catenin when bound to F-actin. Comparisons of wild-type αE-catenin and a mutant with enhanced vinculin affinity using cysteine labeling and isothermal titration calorimetry provide evidence for allosteric coupling of the N-terminal β-catenin-binding and the middle (M) vinculin-binding domain of αE-catenin. Cysteine labeling also revealed possible crosstalk between the actin-binding domain and the rest of the protein. The data provide insight into how binding partners and mechanical stress can regulate the conformation of full-length αE-catenin, and identify the M domain as a key transmitter of conformational changes.
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Affiliation(s)
- Ksenia Terekhova
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Sabine Pokutta
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Yee S Kee
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.,Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (Y.S.K.); Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, 60637 (J.L.), USA
| | - Jing Li
- Departments of Chemistry, Chemical and Biomolecular Engineering, and Center for Biophysics and Quantitative Biology, University of Illinois, Urbana, IL, USA.,Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (Y.S.K.); Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, 60637 (J.L.), USA
| | - Emad Tajkhorshid
- Departments of Chemistry, Chemical and Biomolecular Engineering, and Center for Biophysics and Quantitative Biology, University of Illinois, Urbana, IL, USA
| | - Gerald Fuller
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Alexander R Dunn
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.,Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - William I Weis
- Departments of Structural Biology and Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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30
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Ishiyama N, Sarpal R, Wood MN, Barrick SK, Nishikawa T, Hayashi H, Kobb AB, Flozak AS, Yemelyanov A, Fernandez-Gonzalez R, Yonemura S, Leckband DE, Gottardi CJ, Tepass U, Ikura M. Force-dependent allostery of the α-catenin actin-binding domain controls adherens junction dynamics and functions. Nat Commun 2018; 9:5121. [PMID: 30504777 PMCID: PMC6269467 DOI: 10.1038/s41467-018-07481-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 10/26/2018] [Indexed: 01/26/2023] Open
Abstract
α-catenin is a key mechanosensor that forms force-dependent interactions with F-actin, thereby coupling the cadherin-catenin complex to the actin cytoskeleton at adherens junctions (AJs). However, the molecular mechanisms by which α-catenin engages F-actin under tension remained elusive. Here we show that the α1-helix of the α-catenin actin-binding domain (αcat-ABD) is a mechanosensing motif that regulates tension-dependent F-actin binding and bundling. αcat-ABD containing an α1-helix-unfolding mutation (H1) shows enhanced binding to F-actin in vitro. Although full-length α-catenin-H1 can generate epithelial monolayers that resist mechanical disruption, it fails to support normal AJ regulation in vivo. Structural and simulation analyses suggest that α1-helix allosterically controls the actin-binding residue V796 dynamics. Crystal structures of αcat-ABD-H1 homodimer suggest that α-catenin can facilitate actin bundling while it remains bound to E-cadherin. We propose that force-dependent allosteric regulation of αcat-ABD promotes dynamic interactions with F-actin involved in actin bundling, cadherin clustering, and AJ remodeling during tissue morphogenesis.
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Affiliation(s)
- Noboru Ishiyama
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, M5G 1L7, Canada.
| | - Ritu Sarpal
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Megan N Wood
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | | | - Tadateru Nishikawa
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, M5G 1L7, Canada
| | - Hanako Hayashi
- RIKEN Center for Life Science Technologies, Kobe, Hyogo, 650-0047, Japan
| | - Anna B Kobb
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, M5S 3G9, Canada
| | - Annette S Flozak
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Alex Yemelyanov
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Rodrigo Fernandez-Gonzalez
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, M5S 3G9, Canada
| | - Shigenobu Yonemura
- RIKEN Center for Life Science Technologies, Kobe, Hyogo, 650-0047, Japan
- Department of Cell Biology, Tokushima University Graduate School of Medical Science, Tokushima, 770-8503, Japan
| | - Deborah E Leckband
- Department of Chemistry, University of Illinois, Urbana, IL, 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL, 61801, USA
| | - Cara J Gottardi
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
- Department of Cellular and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Ulrich Tepass
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G5, Canada
| | - Mitsuhiko Ikura
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, M5G 1L7, Canada.
- Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 1L7, Canada.
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31
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32
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Schaffer AE, Breuss MW, Caglayan AO, Al-Sanaa N, Al-Abdulwahed HY, Kaymakçalan H, Yılmaz C, Zaki MS, Rosti RO, Copeland B, Baek ST, Musaev D, Scott EC, Ben-Omran T, Kariminejad A, Kayserili H, Mojahedi F, Kara M, Cai N, Silhavy JL, Elsharif S, Fenercioglu E, Barshop BA, Kara B, Wang R, Stanley V, James KN, Nachnani R, Kalur A, Megahed H, Incecik F, Danda S, Alanay Y, Faqeih E, Melikishvili G, Mansour L, Miller I, Sukhudyan B, Chelly J, Dobyns WB, Bilguvar K, Jamra RA, Gunel M, Gleeson JG. Biallelic loss of human CTNNA2, encoding αN-catenin, leads to ARP2/3 complex overactivity and disordered cortical neuronal migration. Nat Genet 2018; 50:1093-1101. [PMID: 30013181 PMCID: PMC6072555 DOI: 10.1038/s41588-018-0166-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 05/22/2018] [Indexed: 12/12/2022]
Abstract
Neuronal migration defects, including pachygyria, are among the most severe developmental brain defects in humans. Here, we identify biallelic truncating mutations in CTNNA2, encoding αN-catenin, in patients with a distinct recessive form of pachygyria. CTNNA2 was expressed in human cerebral cortex, and its loss in neurons led to defects in neurite stability and migration. The αN-catenin paralog, αE-catenin, acts as a switch regulating the balance between β-catenin and Arp2/3 actin filament activities1. Loss of αN-catenin did not affect β-catenin signaling, but recombinant αN-catenin interacted with purified actin and repressed ARP2/3 actin-branching activity. The actin-binding domain of αN-catenin or ARP2/3 inhibitors rescued the neuronal phenotype associated with CTNNA2 loss, suggesting ARP2/3 de-repression as a potential disease mechanism. Our findings identify CTNNA2 as the first catenin family member with biallelic mutations in humans, causing a new pachygyria syndrome linked to actin regulation, and uncover a key factor involved in ARP2/3 repression in neurons.
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Affiliation(s)
- Ashleigh E Schaffer
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA.
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA.
| | - Martin W Breuss
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Ahmet Okay Caglayan
- Departments of Neurosurgery, Neurobiology, and Genetics, Yale University School of Medicine, New Haven, CT, USA
- Department of Medical Genetics, Istanbul Bilim University, Istanbul, Turkey
| | - Nouriya Al-Sanaa
- Department of Pediatrics, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia
| | - Hind Y Al-Abdulwahed
- Department of Pediatrics, Johns Hopkins Aramco Healthcare, Dhahran, Saudi Arabia
| | - Hande Kaymakçalan
- Department of Pediatrics, Istanbul Bilim University, Istanbul, Turkey
| | - Cahide Yılmaz
- Department of Pediatrics, Yıldırım Beyazıt University, Ankara, Turkey
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Rasim O Rosti
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Brett Copeland
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Seung Tae Baek
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Damir Musaev
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Eric C Scott
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Tawfeg Ben-Omran
- Clinical and Metabolic Genetics Section, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | | | - Hulya Kayserili
- Department of Medical Genetics, Koç University School of Medicine, Istanbul, Turkey
| | | | - Majdi Kara
- University of Tripoli, Tripoli Children's Hospital, Tripoli, Libya
| | - Na Cai
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Jennifer L Silhavy
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Seham Elsharif
- University of Tripoli, Tripoli Children's Hospital, Tripoli, Libya
| | - Elif Fenercioglu
- L.E.S. Mikrogen Genetic Diseases Diagnosis Center, Istanbul, Turkey
| | - Bruce A Barshop
- Department of Pediatrics, Biochemical Genetics Program, University of California, San Diego, San Diego, CA, USA
| | - Bulent Kara
- Department of Pediatric Neurology, Kocaeli University, Kocaeli, Turkey
| | - Rengang Wang
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Valentina Stanley
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Kiely N James
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Rahul Nachnani
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA
| | - Aneesha Kalur
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Hisham Megahed
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Faruk Incecik
- Department of Pediatric Neurology, Cukurova University, Adana, Turkey
| | - Sumita Danda
- Department of Clinical Genetics, Christian Medical College and Hospital, Vellore, India
| | - Yasemin Alanay
- Pediatric Genetics Unit, Department of Pediatrics, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Eissa Faqeih
- Section of Medical Genetics, Department of Pediatrics, King Fahad Medical City, Children's Hospital, Riyadh, Saudi Arabia
| | | | - Lobna Mansour
- Pediatric Department, Neuropediatric Unit, Cairo University Children's Hospital, Cairo, Egypt
| | - Ian Miller
- Neurology Department, Nicklaus Children's Hospital, Miami, FL, USA
| | - Biayna Sukhudyan
- Arabkir Joint Medical Center and Institute of Child and Adolescent Health, Yerevan, Armenia
| | - Jamel Chelly
- Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France
| | - William B Dobyns
- Departments of Pediatrics and Neurology, University of Washington, Seattle, WA, USA
| | - Kaya Bilguvar
- Departments of Neurosurgery, Neurobiology, and Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Rami Abou Jamra
- Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, Germany
| | - Murat Gunel
- Departments of Neurosurgery, Neurobiology, and Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Joseph G Gleeson
- Department of Neuroscience, Rady Children's Institute for Genomic Medicine, Howard Hughes Medical Institute, University of California, San Diego, San Diego, CA, USA.
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Nicholl ID, Matsui T, Weiss TM, Stanley CB, Heller WT, Martel A, Farago B, Callaway DJE, Bu Z. α-Catenin Structure and Nanoscale Dynamics in Solution and in Complex with F-Actin. Biophys J 2018; 115:642-654. [PMID: 30037495 DOI: 10.1016/j.bpj.2018.07.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/17/2018] [Accepted: 07/05/2018] [Indexed: 12/26/2022] Open
Abstract
As a core component of the adherens junction, α-catenin stabilizes the cadherin/catenin complexes to the actin cytoskeleton for the mechanical coupling of cell-cell adhesion. α-catenin also modulates actin dynamics, cell polarity, and cell-migration functions that are independent of the adherens junction. We have determined the solution structures of the α-catenin monomer and dimer using in-line size-exclusion chromatography small-angle X-ray scattering, as well as the structure of α-catenin dimer in complex to F-actin filament using selective deuteration and contrast-matching small angle neutron scattering. We further present the first observation, to our knowledge, of the nanoscale dynamics of α-catenin by neutron spin-echo spectroscopy, which explicitly reveals the mobile regions of α-catenin that are crucial for binding to F-actin. In solution, the α-catenin monomer is more expanded than either protomer shown in the crystal structure dimer, with the vinculin-binding M fragment and the actin-binding domain being able to adopt different configurations. The α-catenin dimer in solution is also significantly more expanded than the dimer crystal structure, with fewer interdomain and intersubunit contacts than the crystal structure. When in complex to F-actin, the α-catenin dimer has an even more open and extended conformation than in solution, with the actin-binding domain further separated from the main body of the dimer. The α-catenin-assembled F-actin bundle develops into an ordered filament packing arrangement at increasing α-catenin/F-actin molar ratios. Together, the structural and dynamic studies reveal that α-catenin possesses dynamic molecular conformations that prime this protein to function as a mechanosensor protein.
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Affiliation(s)
- Iain D Nicholl
- Department of Biomedical Science and Physiology, Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, United Kingdom
| | - Tsutomu Matsui
- Stanford Synchrotron Radiation Light Source, Menlo Park, California
| | - Thomas M Weiss
- Stanford Synchrotron Radiation Light Source, Menlo Park, California
| | | | - William T Heller
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | | | | | - David J E Callaway
- Department of Chemistry and Biochemistry, City College of New York, City University of New York, New York, New York.
| | - Zimei Bu
- Department of Chemistry and Biochemistry, City College of New York, City University of New York, New York, New York.
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34
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Chiarella SE, Rabin EE, Ostilla LA, Flozak AS, Gottardi CJ. αT-catenin: A developmentally dispensable, disease-linked member of the α-catenin family. Tissue Barriers 2018; 6:e1463896. [PMID: 29746206 PMCID: PMC6179130 DOI: 10.1080/21688370.2018.1463896] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/19/2018] [Accepted: 02/23/2018] [Indexed: 02/07/2023] Open
Abstract
α-Catenins are actin-filament binding proteins and critical subunits of the cadherin-catenin cell-cell adhesive complex. They are found in nominally-defined epithelial (E), neural (N), and testis (T) forms transcribed from three distinct genes. While most of α-catenin research has focused on the developmentally essential founding member, αE-catenin, this review discusses recent studies on αT-catenin (CTNNA3), a developmentally dispensable isoform that is emerging as relevant to cardiac, allergic and neurological diseases.
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Affiliation(s)
- Sergio E. Chiarella
- Department of Medicine
- Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Erik E. Rabin
- Department of Medicine
- Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL
| | - Lorena A. Ostilla
- Department of Medicine
- Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Annette S. Flozak
- Department of Medicine
- Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Cara J. Gottardi
- Department of Medicine
- Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL
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35
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Spatial and temporal organization of cadherin in punctate adherens junctions. Proc Natl Acad Sci U S A 2018; 115:E4406-E4415. [PMID: 29691319 DOI: 10.1073/pnas.1720826115] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Adherens junctions (AJs) play a fundamental role in tissue integrity; however, the organization and dynamics of the key AJ transmembrane protein, E-cadherin, both inside and outside of AJs, remain controversial. Here we have studied the distribution and motility of E-cadherin in punctate AJs (pAJs) of A431 cells. Using single-molecule localization microscopy, we show that pAJs in these cells reach more than 1 μm in length and consist of several cadherin clusters with crystal-like density interspersed within sparser cadherin regions. Notably, extrajunctional cadherin appears to be monomeric, and its density is almost four orders of magnitude less than observed in the pAJ regions. Two alternative strategies of tracking cadherin motion within individual junctions show that pAJs undergo actin-dependent rapid-on the order of seconds-internal reorganizations, during which dense clusters disassemble and their cadherins are immediately reused for new clusters. Our results thus modify the classical view of AJs by depicting them as mosaics of cadherin clusters, the short lifetimes of which enable stable overall morphology combined with rapid internal rearrangements.
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36
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The role of adherens junction proteins in the regulation of insulin secretion. Biosci Rep 2018; 38:BSR20170989. [PMID: 29459424 PMCID: PMC5861323 DOI: 10.1042/bsr20170989] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/17/2018] [Accepted: 02/19/2018] [Indexed: 12/16/2022] Open
Abstract
In healthy individuals, any rise in blood glucose levels is rapidly countered by the release of insulin from the β-cells of the pancreas which in turn promotes the uptake and storage of the glucose in peripheral tissues. The β-cells possess exquisite mechanisms regulating the secretion of insulin to ensure that the correct amount of insulin is released. These mechanisms involve tight control of the movement of insulin containing secretory vesicles within the β-cells, initially preventing most vesicles being able to move to the plasma membrane. Elevated glucose levels trigger an influx of Ca2+ that allows fusion of the small number of insulin containing vesicles that are pre-docked at the plasma membrane but glucose also stimulates processes that allow other insulin containing vesicles located further in the cell to move to and fuse with the plasma membrane. The mechanisms controlling these processes are complex and not fully understood but it is clear that the interaction of the β-cells with other β-cells in the islets is very important for their ability to develop the appropriate machinery for proper regulation of insulin secretion. Emerging evidence indicates one factor that is key for this is the formation of homotypic cadherin mediated adherens junctions between β-cells. Here, we review the evidence for this and discuss the mechanisms by which these adherens junctions might regulate insulin vesicle trafficking as well as the implications this has for understanding the dysregulation of insulin secretion seen in pathogenic states.
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37
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Seddiki R, Narayana GHNS, Strale PO, Balcioglu HE, Peyret G, Yao M, Le AP, Teck Lim C, Yan J, Ladoux B, Mège RM. Force-dependent binding of vinculin to α-catenin regulates cell-cell contact stability and collective cell behavior. Mol Biol Cell 2017; 29:380-388. [PMID: 29282282 PMCID: PMC6014167 DOI: 10.1091/mbc.e17-04-0231] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 11/20/2017] [Accepted: 12/14/2017] [Indexed: 11/12/2022] Open
Abstract
Combining cell biology and biomechanical analysis, we show here that the coupling between cadherin complexes and actin through tension-dependent α-catenin/vinculin association is regulating AJ stability and dynamics as well as tissue-scale mechanics. The shaping of a multicellular body and repair of adult tissues require fine-tuning of cell adhesion, cell mechanics, and intercellular transmission of mechanical load. Adherens junctions (AJs) are the major intercellular junctions by which cells sense and exert mechanical force on each other. However, how AJs adapt to mechanical stress and how this adaptation contributes to cell–cell cohesion and eventually to tissue-scale dynamics and mechanics remains largely unknown. Here, by analyzing the tension-dependent recruitment of vinculin, α-catenin, and F-actin as a function of stiffness, as well as the dynamics of GFP-tagged wild-type and mutated α-catenins, altered for their binding capability to vinculin, we demonstrate that the force-dependent binding of vinculin stabilizes α-catenin and is responsible for AJ adaptation to force. Challenging cadherin complexes mechanical coupling with magnetic tweezers, and cell–cell cohesion during collective cell movements, further highlight that tension-dependent adaptation of AJs regulates cell–cell contact dynamics and coordinated collective cell migration. Altogether, these data demonstrate that the force-dependent α-catenin/vinculin interaction, manipulated here by mutagenesis and mechanical control, is a core regulator of AJ mechanics and long-range cell–cell interactions.
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Affiliation(s)
- Rima Seddiki
- Institut Jacques Monod, Centre National de la Recherche Scientifique, CNRS UMR 7592, Université Paris-Diderot, 75205 Paris Cedex 13, France
| | | | - Pierre-Olivier Strale
- Institut Jacques Monod, Centre National de la Recherche Scientifique, CNRS UMR 7592, Université Paris-Diderot, 75205 Paris Cedex 13, France.,Mechanobiology Institute, National University of Singapore, Singapore 117411
| | | | - Grégoire Peyret
- Institut Jacques Monod, Centre National de la Recherche Scientifique, CNRS UMR 7592, Université Paris-Diderot, 75205 Paris Cedex 13, France
| | - Mingxi Yao
- Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - Anh Phuong Le
- Mechanobiology Institute, National University of Singapore, Singapore 117411.,Department of Biomedical Engineering, National University of Singapore, Singapore 117542
| | - Chwee Teck Lim
- Mechanobiology Institute, National University of Singapore, Singapore 117411.,Department of Biomedical Engineering, National University of Singapore, Singapore 117542
| | - Jie Yan
- Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - Benoit Ladoux
- Institut Jacques Monod, Centre National de la Recherche Scientifique, CNRS UMR 7592, Université Paris-Diderot, 75205 Paris Cedex 13, France.,Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - René Marc Mège
- Institut Jacques Monod, Centre National de la Recherche Scientifique, CNRS UMR 7592, Université Paris-Diderot, 75205 Paris Cedex 13, France
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38
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Machesky L, Braga VMM. So far, yet so close: α-Catenin dimers help migrating cells get together. J Cell Biol 2017; 216:3437-3439. [PMID: 29051263 PMCID: PMC5674902 DOI: 10.1083/jcb.201709056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Epithelial cells in tissues use their actin cytoskeletons to stick together, whereas unattached cells make active plasma membrane protrusions to migrate. In this issue, Wood et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201612006) show that the junction component α-catenin is critical in freely moving cells to promote adhesion and migration.
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Affiliation(s)
- Laura Machesky
- Cancer Research UK Beatson Institute, University of Glasgow, Glasgow, Scotland, UK
| | - Vania M M Braga
- National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, England, UK
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39
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Catenins Steer Cell Migration via Stabilization of Front-Rear Polarity. Dev Cell 2017; 43:463-479.e5. [PMID: 29103954 DOI: 10.1016/j.devcel.2017.10.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 09/06/2017] [Accepted: 10/09/2017] [Indexed: 12/19/2022]
Abstract
Cell migration plays a pivotal role in morphogenetic and pathogenetic processes. To achieve directional migration, cells must establish a front-to-rear axis of polarity. Here we show that components of the cadherin-catenin complex function to stabilize this front-rear polarity. Neural crest and glioblastoma cells undergo directional migration in vivo or in vitro. During this process, αE-catenin accumulated at lamellipodial membranes and then moved toward the rear with the support of a tyrosine-phosphorylated β-catenin. This relocating αE-catenin bound to p115RhoGEF, leading to gathering of active RhoA in front of the nucleus where myosin-IIB arcs assemble. When catenins or p115RhoGEF were removed, cells lost the polarized myosin-IIB assembly, as well as the capability for directional movement. These results suggest that, apart from its well-known function in cell adhesion, the β-catenin/αE-catenin complex regulates directional cell migration by restricting active RhoA to perinuclear regions and controlling myosin-IIB dynamics at these sites.
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40
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Wood MN, Ishiyama N, Singaram I, Chung CM, Flozak AS, Yemelyanov A, Ikura M, Cho W, Gottardi CJ. α-Catenin homodimers are recruited to phosphoinositide-activated membranes to promote adhesion. J Cell Biol 2017; 216:3767-3783. [PMID: 28874417 PMCID: PMC5674881 DOI: 10.1083/jcb.201612006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/22/2017] [Accepted: 07/28/2017] [Indexed: 11/22/2022] Open
Abstract
A unique feature of α-catenin localized outside the cadherin-catenin complex is its capacity to form homodimers, but the subcellular localization and functions of this form of α-catenin remain incompletely understood. We identified a cadherin-free form of α-catenin that is recruited to the leading edge of migrating cells in a phosphatidylinositol 3-kinase-dependent manner. Surface plasmon resonance analysis shows that α-catenin homodimers, but not monomers, selectively bind phosphatidylinositol-3,4,5-trisphosphate-containing lipid vesicles with high affinity, where three basic residues, K488, K493, and R496, contribute to binding. Chemical-induced dimerization of α-catenin containing a synthetic dimerization domain promotes its accumulation within lamellipodia and elaboration of protrusions with extended filopodia, which are attenuated in the α-cateninKKR<3A mutant. Cells restored with a full-length, natively homodimerizing form of α-cateninKKR<3A display reduced membrane recruitment, altered epithelial sheet migrations, and weaker cell-cell adhesion compared with WT α-catenin. These findings show that α-catenin homodimers are recruited to phosphoinositide-activated membranes to promote adhesion and migration, suggesting that phosphoinositide binding may be a defining feature of α-catenin function outside the cadherin-catenin complex.
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Affiliation(s)
- Megan N Wood
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL.,The Driskill Graduate Training Program in Life Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Noboru Ishiyama
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Indira Singaram
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL
| | - Connie M Chung
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Annette S Flozak
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Alex Yemelyanov
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL.,Department of Chemistry of Life Processes, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Mitsu Ikura
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON, Canada.,Division of Signaling Biology, Ontario Cancer Institute, University of Toronto, Toronto, ON, Canada
| | - Wonhwa Cho
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL.,Department of Genetic Engineering, Kyung Hee University, Yongin, Republic of Korea
| | - Cara J Gottardi
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL .,Department of Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL
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41
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Maddala R, Rao PV. Switching of α-Catenin From Epithelial to Neuronal Type During Lens Epithelial Cell Differentiation. Invest Ophthalmol Vis Sci 2017; 58:3445-3455. [PMID: 28692740 PMCID: PMC5505122 DOI: 10.1167/iovs.17-21539] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose Ocular lens fiber cell elongation, differentiation, and compaction are associated with extensive reorganization of cell adhesive interactions and cytoskeleton; however, our knowledge of proteins critical to these events is still evolving. This study characterizes the distribution pattern of neuronal-specific α-catenin (αN-catenin) and its interaction with the N-cadherin–associated adherens junctions (AJs) and their stability in the mouse lens fibers. Methods Expression and distribution of αN-catenin in developing mouse and adult human lenses was determined by RT-PCR, immunoblot, and immunofluorescence analyses. Characterization of αN-catenin and N-cadherin interacting proteins and colocalization analyses were performed using immunoprecipitation, mass spectrometry, and confocal imaging. Effects of periaxin deficiency on the stability of lens fiber cell AJs were evaluated using perixin-null mice. Results αN-catenin exhibits discrete distribution to lens fibers in both mouse and human lenses, undergoing a robust up-regulation during fiber cell differentiation and maturation. Epithelial-specific α-catenin (αE-catenin), in contrast, distributes primarily to the lens epithelium. αN-catenin and N-cadherin reciprocally coimmunoprecipitate and colocalize along with β-catenin, actin, spectrin, vinculin, Armadillo repeat protein deleted in velo-cardio-facial syndrome homolog, periaxin, and ankyrin-B in lens fibers. Fiber cells from periaxin-null mouse lenses revealed disrupted N-cadherin/αN-catenin–based AJs. Conclusions These results suggest that the discrete shift in α-catenin expression from αE-catenin to αN-catenin subtype that occurs during lens epithelial cell differentiation may play a key role in fiber cell cytoarchitecture by regulating the assembly and stability of N-cadherin–based AJs. This study also provides evidence for the importance of the fiber cell–specific cytoskeletal interacting periaxin, in the stability of N-cadherin/αN-catenin–based AJs in lens fibers.
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Affiliation(s)
- Rupalatha Maddala
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States 2Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States
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42
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Bachir AI, Horwitz AR, Nelson WJ, Bianchini JM. Actin-Based Adhesion Modules Mediate Cell Interactions with the Extracellular Matrix and Neighboring Cells. Cold Spring Harb Perspect Biol 2017; 9:9/7/a023234. [PMID: 28679638 DOI: 10.1101/cshperspect.a023234] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cell adhesions link cells to the extracellular matrix (ECM) and to each other and depend on interactions with the actin cytoskeleton. Both cell-ECM and cell-cell adhesion sites contain discrete, yet overlapping, functional modules. These modules establish physical associations with the actin cytoskeleton, locally modulate actin organization and dynamics, and trigger intracellular signaling pathways. Interplay between these modules generates distinct actin architectures that underlie different stages, types, and functions of cell-ECM and cell-cell adhesions. Actomyosin contractility is required to generate mature, stable adhesions, as well as to sense and translate the mechanical properties of the cellular environment into changes in cell organization and behavior. Here, we review the organization and function of different adhesion modules and how they interact with the actin cytoskeleton. We highlight the molecular mechanisms of mechanotransduction in adhesions and how adhesion molecules mediate cross talk between cell-ECM and cell-cell adhesion sites.
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Affiliation(s)
- Alexia I Bachir
- Protein and Cell Analysis, Biosciences Division, Thermo Fisher Scientific, Eugene, Oregon 97402
| | - Alan Rick Horwitz
- Protein and Cell Analysis, Biosciences Division, Thermo Fisher Scientific, Eugene, Oregon 97402
| | - W James Nelson
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22903
| | - Julie M Bianchini
- Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22903
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43
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Jégou A, Romet-Lemonne G. Single Filaments to Reveal the Multiple Flavors of Actin. Biophys J 2017; 110:2138-46. [PMID: 27224479 DOI: 10.1016/j.bpj.2016.04.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 03/26/2016] [Accepted: 04/01/2016] [Indexed: 11/29/2022] Open
Abstract
A number of key cell processes rely on specific assemblies of actin filaments, which are all constructed from nearly identical building blocks: the abundant and extremely conserved actin protein. A central question in the field is to understand how different filament networks can coexist and be regulated. Discoveries in science are often related to technical advances. Here, we focus on the ongoing single filament revolution and discuss how these techniques have greatly contributed to our understanding of actin assembly. In particular, we highlight how they have refined our understanding of the many protein-based regulatory mechanisms that modulate actin assembly. It is now becoming apparent that other factors give filaments a specific identity that determines which proteins will bind to them. We argue that single filament techniques will play an essential role in the coming years as we try to understand the many ways actin filaments can take different flavors and unveil how these flavors modulate the action of regulatory proteins. We discuss different factors known to make actin filaments distinguishable by regulatory proteins and speculate on their possible consequences.
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Affiliation(s)
- Antoine Jégou
- Institut Jacques Monod, CNRS, Université Paris Diderot, Université Sorbonne Paris Cité, Paris, France
| | - Guillaume Romet-Lemonne
- Institut Jacques Monod, CNRS, Université Paris Diderot, Université Sorbonne Paris Cité, Paris, France.
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44
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Abstract
Filamentous actin (F-actin) organization within cells is regulated by a large number of actin-binding proteins that control actin nucleation, growth, cross-linking and/or disassembly. This protocol describes a technique – the actin co-sedimentation, or pelleting, assay – to determine whether a protein or protein domain binds F-actin and to measure the affinity of the interaction (i.e., the dissociation equilibrium constant). In this technique, a protein of interest is first incubated with F-actin in solution. Then, differential centrifugation is used to sediment the actin filaments, and the pelleted material is analyzed by SDS-PAGE. If the protein of interest binds F-actin, it will co-sediment with the actin filaments. The products of the binding reaction (i.e., F-actin and the protein of interest) can be quantified to determine the affinity of the interaction. The actin pelleting assay is a straightforward technique for determining if a protein of interest binds F-actin and for assessing how changes to that protein, such as ligand binding, affect its interaction with F-actin.
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Affiliation(s)
- Jonathon A Heier
- Department of Cell Biology, University of Pittsburgh School of Medicine
| | | | - Adam V Kwiatkowski
- Department of Cell Biology, University of Pittsburgh School of Medicine;
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45
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Mège RM, Ishiyama N. Integration of Cadherin Adhesion and Cytoskeleton at Adherens Junctions. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a028738. [PMID: 28096263 DOI: 10.1101/cshperspect.a028738] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The cadherin-catenin adhesion complex is the key component of the intercellular adherens junction (AJ) that contributes both to tissue stability and dynamic cell movements in epithelial and nonepithelial tissues. The cadherin adhesion complex bridges neighboring cells and the actin-myosin cytoskeleton, and thereby contributes to mechanical coupling between cells which drives many morphogenetic events and tissue repair. Mechanotransduction at cadherin adhesions enables cells to sense, signal, and respond to physical changes in their environment. Central to this process is the dynamic link of the complex to actin filaments (F-actin), themselves structurally dynamic and subject to tension generated by myosin II motors. We discuss in this review recent breakthroughs in understanding molecular and cellular aspects of the organization of the core cadherin-catenin complex in adherens junctions, its association to F-actin, its mechanosensitive regulation, and dynamics.
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Affiliation(s)
- René Marc Mège
- Institut Jacques Monod (IJM), CNRS UMR 7592 and Université Paris Diderot, Paris, France
| | - Noboru Ishiyama
- Princess Margaret Cancer Centre, University Health Network, TMDT 4-902, Toronto, Ontario, Canada
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46
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Spatial integration of E-cadherin adhesion, signalling and the epithelial cytoskeleton. Curr Opin Cell Biol 2016; 42:138-145. [DOI: 10.1016/j.ceb.2016.07.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/22/2016] [Accepted: 07/08/2016] [Indexed: 12/18/2022]
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47
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Clarke DN, Miller PW, Lowe CJ, Weis WI, Nelson WJ. Characterization of the Cadherin-Catenin Complex of the Sea Anemone Nematostella vectensis and Implications for the Evolution of Metazoan Cell-Cell Adhesion. Mol Biol Evol 2016; 33:2016-29. [PMID: 27189570 PMCID: PMC4948710 DOI: 10.1093/molbev/msw084] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The cadherin-catenin complex (CCC) mediates cell-cell adhesion in bilaterian animals by linking extracellular cadherin-based adhesions to the actin cytoskeleton. However, it is unknown whether the basic organization of the complex is conserved across all metazoans. We tested whether protein interactions and actin-binding properties of the CCC are conserved in a nonbilaterian animal, the sea anemone Nematostella vectensis We demonstrated that N. vectensis has a complete repertoire of cadherin-catenin proteins, including two classical cadherins, one α-catenin, and one β-catenin. Using size-exclusion chromatography and multi-angle light scattering, we showed that α-catenin and β-catenin formed a heterodimer that bound N. vectensis Cadherin-1 and -2. Nematostella vectensis α-catenin bound F-actin with equivalent affinity as either a monomer or an α/β-catenin heterodimer, and its affinity for F-actin was, in part, regulated by a novel insert between the N- and C-terminal domains. Nematostella vectensis α-catenin inhibited Arp2/3 complex-mediated nucleation of actin filaments, a regulatory property previously thought to be unique to mammalian αE-catenin. Thus, despite significant differences in sequence, the key interactions of the CCC are conserved between bilaterians and cnidarians, indicating that the core function of the CCC as a link between cell adhesions and the actin cytoskeleton is ancestral in the eumetazoans.
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Affiliation(s)
| | - Phillip W Miller
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine
| | | | - William I Weis
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine Department of Structural Biology, Stanford University School of Medicine
| | - William James Nelson
- Department of Biology, Stanford University Department of Molecular and Cellular Physiology, Stanford University School of Medicine
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48
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Dong JM, Tay FPL, Swa HLF, Gunaratne J, Leung T, Burke B, Manser E. Proximity biotinylation provides insight into the molecular composition of focal adhesions at the nanometer scale. Sci Signal 2016; 9:rs4. [PMID: 27303058 DOI: 10.1126/scisignal.aaf3572] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Focal adhesions are protein complexes that link metazoan cells to the extracellular matrix through the integrin family of transmembrane proteins. Integrins recruit many proteins to these complexes, referred to as the "adhesome." We used proximity-dependent biotinylation (BioID) in U2OS osteosarcoma cells to label proteins within 15 to 25 nm of paxillin, a cytoplasmic focal adhesion protein, and kindlin-2, which directly binds β integrins. Using mass spectrometry analysis of the biotinylated proteins, we identified 27 known adhesome proteins and 8 previously unknown components close to paxillin. However, only seven of these proteins interacted directly with paxillin, one of which was the adaptor protein Kank2. The proteins in proximity to β integrin included 15 of the adhesion proteins identified in the paxillin BioID data set. BioID also correctly established kindlin-2 as a cell-cell junction protein. By focusing on this smaller data set, new partners for kindlin-2 were found, namely, the endocytosis-promoting proteins liprin β1 and EFR3A, but, contrary to previous reports, not the filamin-binding protein migfilin. A model adhesome based on both data sets suggests that focal adhesions contain fewer components than previously suspected and that paxillin lies away from the plasma membrane. These data not only illustrate the power of using BioID and stable isotope-labeled mass spectrometry to define macromolecular complexes but also enable the correct identification of therapeutic targets within the adhesome.
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Affiliation(s)
- Jing-Ming Dong
- sGSK Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Proteos Building, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Felicia Pei-Ling Tay
- sGSK Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Proteos Building, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Hannah Lee-Foon Swa
- Quantitative Proteomics Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Singapore 138673, Singapore
| | - Jayantha Gunaratne
- Quantitative Proteomics Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Singapore 138673, Singapore. Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Thomas Leung
- sGSK Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Proteos Building, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Brian Burke
- Institute of Medical Biology, 8A Biomedical Grove, #06-06 Immunos Building, Singapore 138648, Singapore
| | - Ed Manser
- sGSK Group, Institute of Molecular and Cell Biology, Agency for Science Technology and Research, Proteos Building, 61 Biopolis Drive, Singapore 138673, Singapore. Institute of Medical Biology, 8A Biomedical Grove, #06-06 Immunos Building, Singapore 138648, Singapore. Department of Pharmacology, National University of Singapore, Singapore 117597, Singapore.
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49
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Schwayer C, Sikora M, Slováková J, Kardos R, Heisenberg CP. Actin Rings of Power. Dev Cell 2016; 37:493-506. [DOI: 10.1016/j.devcel.2016.05.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/24/2016] [Accepted: 05/25/2016] [Indexed: 12/21/2022]
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50
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Wickline ED, Dale IW, Merkel CD, Heier JA, Stolz DB, Kwiatkowski AV. αT-Catenin Is a Constitutive Actin-binding α-Catenin That Directly Couples the Cadherin·Catenin Complex to Actin Filaments. J Biol Chem 2016; 291:15687-99. [PMID: 27231342 PMCID: PMC4957052 DOI: 10.1074/jbc.m116.735423] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Indexed: 11/06/2022] Open
Abstract
α-Catenin is the primary link between the cadherin·catenin complex and the actin cytoskeleton. Mammalian αE-catenin is allosterically regulated: the monomer binds the β-catenin·cadherin complex, whereas the homodimer does not bind β-catenin but interacts with F-actin. As part of the cadherin·catenin complex, αE-catenin requires force to bind F-actin strongly. It is not known whether these properties are conserved across the mammalian α-catenin family. Here we show that αT (testes)-catenin, a protein unique to amniotes that is expressed predominantly in the heart, is a constitutive actin-binding α-catenin. We demonstrate that αT-catenin is primarily a monomer in solution and that αT-catenin monomer binds F-actin in cosedimentation assays as strongly as αE-catenin homodimer. The β-catenin·αT-catenin heterocomplex also binds F-actin with high affinity unlike the β-catenin·αE-catenin complex, indicating that αT-catenin can directly link the cadherin·catenin complex to the actin cytoskeleton. Finally, we show that a mutation in αT-catenin linked to arrhythmogenic right ventricular cardiomyopathy, V94D, promotes homodimerization, blocks β-catenin binding, and in cardiomyocytes disrupts localization at cell-cell contacts. Together, our data demonstrate that αT-catenin is a constitutively active actin-binding protein that can physically couple the cadherin·catenin complex to F-actin in the absence of tension. We speculate that these properties are optimized to meet the demands of cardiomyocyte adhesion.
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Affiliation(s)
- Emily D Wickline
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Ian W Dale
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Chelsea D Merkel
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Jonathon A Heier
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Donna B Stolz
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Adam V Kwiatkowski
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
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